The main difficulty in packaging high frequency power transformers and multi-winding inductors for surface mounted device applications is to provide accurate coplanarity of the device terminals during manufacturing and installation on the mounting surface or substrate. Prior art headers have used a solid plastic base with molded copper or brass terminals to prevent terminal to wire or terminal to planar winding connection from re-flow during installation and losing coplanarity with other terminals and with the bottom of the core. The ferrite cores have been mounted on the top of the plastic header or base. These prior art devices have been a problem in many applications because of the height of the device makes it unsuitable or difficult to use in low profile converters and power supplies. In addition, these prior art devices have presented cooling problems in that the plastic header between the core and the substrate acts as a thermal barrier. This cooling problem has been solved in the past by either de-rating the surface mount device, thus increasing the cost and the size of the power converter, or by using other cooling methods such as fans.
Other prior art devices have used separate surface mount strips with terminals for the primary and secondary sides of transformers. Although this configuration solves the problem of cooling the core and meets the coplanarity requirement between primary pins or secondary pins, it does not solve the problem of coplanarity between all of the terminals, that is, the primary and secondary sides, as well as the core.
Accordingly, there has been a long felt need in the art to provide a surface mount magnetic component assembly that provides coplanarity between all of the pins and the core, that presents a low profile, and that provides improved cooling capabilities.